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Date:   Tue, 04 Aug 2020 19:20:05 -0700 (PDT)
Subject:     Re: [PATCH 1/2] riscv: ptrace: Use the correct API for `fcsr' access
In-Reply-To: <20200805020745.GL1236603@ZenIV.linux.org.uk>
CC:     macro@wdc.com, linux-riscv@lists.infradead.org,
        Paul Walmsley <paul.walmsley@sifive.com>,
        aou@eecs.berkeley.edu, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org
From:   Palmer Dabbelt <palmer@dabbelt.com>
To:     viro@zeniv.linux.org.uk
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On Tue, 04 Aug 2020 19:07:45 PDT (-0700), viro@zeniv.linux.org.uk wrote:
> On Tue, Aug 04, 2020 at 07:01:01PM -0700, Palmer Dabbelt wrote:
>
>> > We currently have @start_pos fixed at 0 across all calls, which works as
>> > a result of the implementation, in particular because we have no padding
>> > between the FP general registers and the FP control and status register,
>> > but appears not to have been the intent of the API and is not what other
>> > ports do, requiring one to study the copy handlers to understand what is
>> > going on here.
>
> start_pos *is* fixed at 0 and it's going to go away, along with the
> sodding user_regset_copyout() very shortly.  ->get() is simply a bad API.
> See vfs.git#work.regset for replacement.  And ->put() is also going to be
> taken out and shot (next cycle, most likely).

I'm not sure I understand what you're saying, but given that branch replaces
all of this I guess it's best to just do nothing on our end here?